A non-transitory computer readable medium having computer executable instructions stored thereon is provided. The computer executable instructions include a mission definition file (mdf) that includes mission data that describes alternative routes generated by at least one mission planner for a vehicle. An mdf parser extracts the mission data for the alternative routes from the mdf and maps the mission data into a temporal data structure describing the alternative routes. The temporal data includes a route list to describe the alternative routes for the vehicle and a route segment list to describe an estimated time between each of the waypoints for each segment of the route list. A waypoint list describes a latitude, a longitude, and an altitude for each of the waypoints and a mission plan constructor generates a network topology of a mission plan depicting the alternative routes for the vehicle over time.
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18. A method, comprising:
parsing a mission data file into an initial temporal data structure establishing a mission network structure;
extrapolating estimated segment transition times for each segment of the mission network structure;
extracting task timing constraints from input tasking to populate an action list;
extracting specified task constraints to populate an action point data list; and
outputting the temporal data structure after populating the lists, the temporal data structure comprising:
the action list and the action data point list;
a route list to describe alternative routes for the vehicle, each alternative route defined by at least one segment to connect between waypoints;
a route segment list to describe an estimated time between each of the waypoints for each segment of the route list; and
a waypoint list to describe a latitude, a longitude, and an altitude for each of the waypoints for each segment of the route list;
determining, during a real-time mission associated with the at least one primary route, whether or not a planned action at a future time on at least one of the alternative routes satisfies a timing constraint for the mission plan; and
displaying, during the real-time mission, a current position of the vehicle, the alternative routes for the vehicle, and an indication whether or not the planned action on the at least one of the alternative routes satisfies the timing constraint for the mission plan to facilitate selection of a respective one of the alternative routes.
1. A non-transitory computer readable medium having computer executable instructions stored thereon, the computer executable instructions comprising:
a mission definition file (mdf) that includes mission data that describes at least one primary route and alternative routes generated by at least one mission planner for a vehicle;
a mdf parser to extract the mission data for the at least one primary route and the alternative routes from the mission definition file, the mdf parser maps the mission data into a temporal data structure describing the at least one primary route and the alternative routes;
the temporal data structure comprising:
a route list to describe the at least one primary route and the alternative routes for the vehicle, each alternative route defined by at least one segment to connect between waypoints;
a route segment list to describe an estimated time between each of the waypoints for each segment of the route list; and
a waypoint list to describe a latitude, a longitude, and an altitude for each of the waypoints for each segment of the route list;
a mission plan constructor to generate a network topology of a mission plan depicting the at least one primary route and the alternative routes for the vehicle over time by graphing list data from the temporal data structure for the alternative routes;
an automated module to determine, during a real-time mission associated with the at least one primary route, whether or not a planned action at a future time on at least one of the alternative routes satisfies a timing constraint for the mission plan; and
a graphical user interface that displays, during the real-time mission, a current position of the vehicle, the alternative routes for the vehicle, and an indication whether or not the planned action on the at least one of the alternative routes satisfies the timing constraint for the mission plan to facilitate selection of a respective one of the alternative routes.
11. A system, comprising:
a memory to store computer-executable instructions; and
a processor to execute the computer-executable instructions from the memory, the computer-executable instructions comprising:
a mission definition file (mdf) that includes mission data that describes at least one primary route and alternative routes generated by at least one mission planner for a vehicle;
a mdf parser to extract the mission data for the at least one primary route and the alternative routes from the mission definition file, the mdf parser maps the mission data into a temporal data structure describing the at least one primary route and the alternative routes;
the temporal data structure comprising:
a route list to describe the alternative routes for the vehicle, each alternative route defined by at least one segment to connect between waypoints;
a route segment list to describe an estimated time between each of the waypoints for each segment of the route list; and
a waypoint list to describe a latitude, a longitude, and an altitude for each of the waypoints for each segment of the route list; and
a mission plan constructor to generate a network topology of a mission plan depicting the at least one primary route and the alternative routes for the vehicle over time by graphing list data from the temporal data structure for the alternative routes;
an automated module to determine, during a real-time mission associated with the at least one primary route, whether or not a planned action at a future time on at least one of the alternative routes satisfies a timing constraint for the mission plan; and
a graphical user interface (GUI) to display a visualization of the network topology generated by the mission plan constructor from the temporal data structure, wherein the at least one primary route and the alternative routes can be viewed concurrently in the visualization to enable determination of a what-if alternative mission plan scenario that satisfy the timing constraint for the mission plan for the one or more vehicles to facilitate selection of a respective one of the alternative routes.
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This disclosure relates to manned and unmanned vehicle interfaces, and more particularly to a system and method to provide temporal data structures to enable analysis and comparison of alternative mission plans of manned and unmanned vehicles over time.
Typical mission plan interface software for a general manned or unmanned vehicle allows operators to plan the tasks to be executed by each vehicle via a graphical user interface that includes various input and output options for feedback and control of the planning process. The graphical user interface typically provides a three-dimensional presentation that includes latitude, longitude, and altitude information in the display output relating to a proposed mission plan during pre-mission planning and also allows monitoring and control of real-time mission progress during mission execution. This includes updating way points, aborting plans, allowing manual override, and so forth. Typical graphical user interfaces to existing mission planning and control systems have limited abilities to analyze how changes to the current environment will impact tasks planned for execution in the future. This usually consists of limited abilities to visually compare the current iteration of a single plan for a single vehicle with the previous iteration of the same plan. Comparison is typically performed visually by a human operator comparing the route and each individual task within the mission plan against defined mission success criteria. Some methods attempt to provide computational metrics that quantify the performance of one or more aspects of the mission plan. These current methods are slow and manually cumbersome at evaluating the mission plan's performance for a single vehicle. Current methods are also typically tied to a single mission planner designed for a single specific vehicle further restricting their ability to evaluate alternatives for other vehicles of the same domain type or other vehicles of different domain types.
One issue with current vehicle interface software is that new plans or alternative options to existing plans are developed by mission planning systems that do not export time as an explicit parameter of the mission plan. While the notion of time is used internally by the mission planning system when planning a mission, the lack of time as a specific output parameter in the mission plan makes evaluation of timing constraints for a single plan difficult and comparison of alternative options extremely complex. This results in longer plan evaluation and approval times having negative consequences in time constrained environments.
This disclosure relates to temporal data structures to enable analysis and comparison of alternative mission plans of manned and unmanned vehicles over time. In one example, a non-transitory computer readable medium is provided having computer executable instructions stored thereon. The computer executable instructions include a mission definition file (MDF) that includes mission data that describes alternative routes generated by at least one mission planner for a vehicle. An MDF parser extracts the mission data for the alternative routes from the MDF. The MDF parser maps the mission data into a temporal data structure describing the alternative routes. The temporal data structure includes a route list to describe the alternative routes for the vehicle. Each alternative route is defined by at least one segment to connect between waypoints. A route segment list describes an estimated time between each of the waypoints for each segment of the route list. A waypoint list describes a latitude, a longitude, and an altitude for each of the waypoints for each segment of the route list. A mission plan constructor generates a network topology of a mission plan depicting the alternative routes for the vehicle over time by graphing list data from the temporal data structure for the alternative routes.
In another example, a system includes a memory to store computer-executable instructions a processor to execute the computer-executable instructions from the memory. The computer-executable instructions include a mission definition file (MDF) that includes mission data that describes alternative routes generated by at least one mission planner for a vehicle. An MDF parser extracts the mission data for the alternative routes from the MDF. The MDF parser maps the mission data into a temporal data structure describing the alternative routes. The temporal data structure includes a route list to describe the alternative routes for the vehicle. Each alternative route is defined by at least one segment to connect between waypoints. A route segment list describes an estimated time between each of the waypoints for each segment of the route list. A waypoint list describes a latitude, a longitude, and an altitude for each of the waypoints for each segment of the route list. A mission plan constructor generates a network topology of a mission plan depicting the alternative routes for the vehicle over time by graphing list data from the temporal data structure for the alternative routes. A graphical user interface (GUI) displays a visualization of the network topology generated by the mission plan constructor from the temporal data structure. The alternative routes can be viewed concurrently in the visualization to enable determination of what-if alternative mission plan scenarios for the one or more vehicles.
In yet another example, a method includes parsing a mission data file into an initial temporal data structure establishing a mission network structure. The method includes extrapolating estimated segment transition times for each segment of the mission network structure. This includes extracting task timing constraints from input tasking to populate an action list. The method includes extracting specified task constraints to populate an action point data list. The method includes outputting the temporal data structure after populating the lists. The temporal data structure includes the action list and the action data point list. This includes a route list to describe alternative routes for the vehicle. Each alternative route is defined by at least one segment to connect between waypoints. A route segment list describes an estimated time between each of the waypoints for each segment of the route list. A waypoint list describes a latitude, a longitude, and an altitude for each of the waypoints for each segment of the route list.
This disclosure relates to manned and unmanned vehicle interfaces, and more particularly to a system and method to provide temporal data structures to enable analysis and comparison of alternative mission plans of manned and unmanned vehicles over time. The data structures enable automated modules to determine when planned actions will be performed as well as to automatically project the execution time of planned actions into the future driven by changes to the timing of events occurring prior to the planned actions. Temporal data structures can be constructed to enable analysis and comparison of alternative mission plans of manned and unmanned vehicles over time. Mission plans consist of one or more tasks to be executed and one or more routes for vehicles to traverse to accomplish such tasking. The data structures and associated interfaces are independent of any one mission planning system and any one vehicle domain type. This can be used in all phases of a mission including pre-mission planning, real-time mission execution, and post-mission analysis, for example.
In one aspect, a non-transitory computer readable medium having computer executable instructions stored thereon is provided. The computer executable instructions include a Mission Definition File (MDF) that includes mission data that describes alternative plans generated by at least one mission planner for at least one vehicle. If desired, one of the alternative plans can be designated as the primary route. A four dimensional (4D) mission plan constructor parses the MDF and extracts the mission data for the alternative plans that may be included from the mission definition file. The 4D mission plan constructor maps the mission data into a 4D temporal data structure describing the alternative plans that may exist. Items in the 4D data structure that are not directly mapped back to items in the MDF, such as Estimated Transit Times (ETT) of specific portions of a mission route, can either be extrapolated from exiting data items in the MDF or computed using models of the vehicle, environmental models, and mathematical time extrapolation methods over distances traversed.
The temporal data structure (also referred to as 4D data structure) makes time an explicit parameter enabling automated methods to perform analysis and comparison of multiple plan alternatives. The 4D data structure captures the topology of a mission plan and all its alternative options in a network structure. Included in the topology are estimated times of arrival at intermediate points in the plan as well as estimated transit times along the various plan segments. Times of planned actions are specified as offsets from various estimated time of arrival points. This enables determination of the absolute time the action is planned to be performed by a straight-forward addition and the ability to project the execution of the planned action to some point in the future given changes to the timing of events occurring prior to the planned action. This explicit use of time estimation and execution time projection enables automated modules to determine if a specific action in the plan can be expected to be executed at the time specified. Also, if the automated modules detect that an action will not be executed as planned, they can predict how much sooner or later than planned the action can be performed. This enables a system to provide automated alerts to the operator raising awareness that an action planned in the future may not be executed by the time specified. Since the 4D data structure is vehicle independent, different plans for different vehicles can be compared to determine which vehicle satisfies or fails to satisfy specified timing criteria.
By adding time to the temporal data structure, not only are three dimensional positional coordinates accounted for in the mission network topology but a fourth dimensional (4D) component specifying a planned time for execution of mission actions is also provided. The data structures provide a common data model to enable construction of visualizations depicting alternative plan actions for analysis and comparison. This allows mission operators to conduct what-if scenario analysis of current or alternative mission plans in a rapid and cognitively digestible manner. Thus, the data structures provide a common format in which to map disparate mission data from independent external mission planners. The common data format also enables rapid construction of fused visualizations of primary and alternative plans of manned and unmanned vehicles since each component of the visualization can be constructed from the same common data format.
The system 100 includes two or more cooperating modules to generate the temporal data structures described herein. These modules include a 4D mission plan constructor 110 and at least one independent mission planning system 112 that generates one or more mission plans for one or more vehicles. The output of the mission planning system 112 is a Mission Data File (MDF) 114 that includes at least one primary mission plan for at least one vehicle. The MDF 114 may include multiple mission plan alternatives, including contingency plans that account for various vehicle failure scenarios, in addition to the primary mission plan. In another example, there may exist multiple independent mission planning systems 112 each producing one or more mission plans and alternatives for one or more vehicles of various types and in various domains (e.g., land, sea, air, space).
Each mission planning system 112 generates its plans driven by input tasking 116 provided by an external entity. For military operations, tasking inputs 116 may come from a central command authority while for commercial operations, tasking may come from a central or distributed order processing system. In most examples, specific tasking 116 is specified to the mission planning system 112 along with associated tasking priorities and optional additional tasking constraints. Execution timing is often an additional constraint placed on input tasking requests 116 and can take the form of specifying a No-Sooner-Than (NST) time of arrival, a No-Later-Than (NLT) delivery of a package, or a fixed time window within which a task may only be performed including both NST and NLT constrained situations.
In addition to tasking requests, priorities, and constraints 116, environmental planning data 118 is also used by the mission planning system 112 when generating a mission plan. Environmental planning data 118 can include orbital models and gravitational field models for space vehicles, wind velocity vectors, air temperature, and pressure for air vehicles, sea state and sea currents for sea surface vehicles, sea temperature and currents for undersea vehicles, and/or terrain models and road networks for ground vehicles, for example.
The 4D mission plan constructor 110 of system 100 uses the input tasking, priorities and constraints 116, the environmental planning data 118, along with the mission plans contained in the mission data files 114 output by the one or more mission planning systems 112 to construct 4D mission plan data structures 119. The mission data contained within the MDF 114 is parsed by one or more MDF parsers 120. Since each independent mission planning system 112 will likely output a different MDF format, the MDF parser 120 can parse each of the formats (e.g., via mapping tables that map one MDF data entry to a common data format). As the mission data is parsed from the MDF 114, an initial 4D data structure is populated with the mission data that exists.
Since conventional mission planners 112 do not output time as an explicit parameter of their mission plans, time extrapolation engines 130 can be employed to estimate the intermediate times of arrival for vehicles from a current location or waypoint to a subsequent location or waypoint. These engines 130 can include but are not limited to, Kalman filters, Markov filters, Particle filters, Runga-Kutta, Predictor-Corrector, and so forth, for example. The time extrapolation engines 130 can employ vehicle models 140 and environmental models 150 as needed. Vehicle models 140 are vehicle specific and model the physical ability of the vehicle to move over time. Environmental models 150 model environmental effects on vehicle movement. For example, a wind forecast model consisting of wind direction and velocity at mission time in the mission area can be used together with a vehicle model 140 by the time extrapolation engine 130 to estimate times of arrival of a specific air vehicle traveling on its planned route. A system for updating such environmental vehicle models is illustrated and described below with respect to
After completing the estimation of the timing parameters in the 4D mission plan data structure 119, the 4D mission plan constructor 110 adds in the timing constraints specified in the input tasking 116 to the data structure. While not every task in the mission plan will have a timing constraint, those that do can be incorporated into the 4D data structure 119. After completing adding the timing constraints to the 4D data structure, the 4D mission plan data structure 119 is output from the 4D mission plan constructor 110 where it can be employed to generate visualizations of alternative plans for analysis as described herein.
The network topology of 200 defines three routes in this example: R1, R2, and R3, however more or less routes are possible. Each route is specified in a route list 230 by an ordered list of route segments. The routes specified in the route list 230 consist of at least one primary route and optional alternative routes that can be contingency routes or simple alternatives to the primary plan should certain conditions become satisfied during mission execution. In the example of
Another construct of the network topology 200 is a route leg list 240. The route leg list 240 enables the specification of portions of the network topology 200 that represent specific activities of the mission plan that the operator wants to pay additional attention to and perhaps perform additional analysis of. In the example of
The activities for each action points defined in the route activities lists 320, 330, and 340, are specified in an action point list 350. The action point list 350 is a tuple specifying delta time (DT), time constraint (TC), a time specification (TS), an action command (CMD), and data (DATA) needed to execute the command (CMD). In the example illustrated, segment s1 of route R1 activities list 320, specifies action point AP111 as a planned action. Action point list 350 specifies action point AP111 occurs 30 seconds (DT=00:00:30) after capturing the starting waypoint wp1, specified on route segment list 230 of
By specifying the example network topology of a mission in the manner described in
In view of the foregoing structural and functional features described above, an example method will be better appreciated with reference to
The temporal data structure includes the action list and the action data point list. This includes a route list to describe alternative routes for the vehicle. Each alternative route is defined by at least one segment to connect between waypoints. A route segment list describes an estimated time between each of the waypoints for each segment of the route list. A waypoint list describes a latitude, a longitude, and an altitude for each of the waypoints for each segment of the route list. The method 400 can also include updating the route segment list to include a list of segments with each segment defined as two waypoints, each of the two waypoints having an estimated time of arrival field to denote the estimated time elapsed to travel between the two waypoints.
Future actions that are to be performed for each plan are depicted as grey triangles with lines indicating where along the plan they are to be performed. In the example of
The state aggregator 614 receives and processes the various data feeds that constitute a mission. It is generally always on and is processing in real time. It provides the current world state to the HMI 610 and the prediction engine 618. The HMI 610 provides situational awareness in real time of the current world state and can provide fused visualizations of the current world state and alternative future world states. The HMI 610 also includes graphical tools 628 to allow an operator to control the prediction engine 618 enabling the generation of alternative plans projected into the future. The prediction engine 618 has access to the current world state, alternative plans, and receives operator inputs to project the current world state and alternative plans to some point in the future. The prediction engine 618 provides the projected future world state and any projected alternatives to the HMI 610 for fusion and display to the operator 626.
The state aggregator 614 includes static and real-time data feeds that constitute a mission and are received via adapter modules 630 which are processed via world state manager 634. The data feeds can include a mission plan. This data feed originates from various mission planning engines in various formats, and includes the primary route and contingency routes for each platform. Furthermore, it includes the state of a platform (position, velocity, orientation, fuel, and so forth) at periodic increments. This is true for each manned or unmanned vehicle platform along the primary route and contingency routes.
A tasking data feed originates external to the system in various formats and consists of actions to perform. These actions may include Intelligence Surveillance and Reconnaissance (ISR) collections, strike (both kinetic and electronic), communications relay, and the delivery of a payload such as fuel or supplies. Tasking can have constraints that may include a time window within which the action must take place; a location where the action must be performed; and detailed geometric constraints that may include azimuth, elevation, and velocity with respect to the tasking, for example. A weather data feed originates external to the system in various formats and consists of information pertaining to winds, currents, cloud coverage, temperature, humidity, and precipitation. Weather feeds include both current measurements and forecasted conditions.
A threats data feed originates external to the system in various formats and includes threat information (e.g., type of threat, location, and range of threat effectiveness). Threats may also include environmental obstacles such as terrain, bodies of water, icebergs, and cultural obstacles such as power lines, buildings, and towers. A tracks data feed originates external to the system in various formats and includes track information (e.g., entity type, hostile/friendly, location, velocity, orientation). A sensors data feed is per payload type for each asset and consists of data for field of view and field of regard data on position and orientation of the sensor. A COMMS data feed provides they type of communications asset available and its current and planned footprint over time.
Because each of the data feeds delineated above has multiple formats and can change in real-time, and independently of one another, adapters 630 have been created to mediate the various data types to an internal standardized data model managed by the world state manager 634. The world state manager 634 has the responsibility to aggregate the disparate data feeds into a single internal representation and at a single point in time as well as store and manage the internal data model. By extension, other inputs and data feeds may also be aggregated into the internal data model as needed through additional adapters 630.
At a particular time instance, t(i), the aggregation of all the data as captured constitutes the present world state 640 which can be utilized to update contingency data within the data structures described herein (e.g., via the behavior fields). This present world state 640 is updated in real time and, at a minimum, is updated at a 1 Hz rate, for example. The present world state snapshot is made available to the HMI's fusion and rendering pipeline component 620 which automatically renders the state onto a physical display device for the operator 626 to view. The present world state 634 is also provided to the prediction engine 618 for propagation into some future time t(f) specified by the operator.
As noted above, the HMI 610 includes the world state fusion & rendering pipeline 620 which is an event driven component that receives world state updates or changes made by the state aggregator 614 to the present world state 614. It also has the responsibility of fusing the current world state with future world state generated by the prediction engine 618 and rendering the resultant fused information onto the physical display device 624 for the operator 626 to view. The graphical input tools 628 houses graphical components that take inputs from an operator 626. A notional example of an input tool is a timeline slider. This input component displays current time, which is always moving forward, and a future time, which is calculated by an offset that is determined by the operator through sliding a marker along the timeline, in one example. When the operator 626 requests a projection of the world state by method of a graphical input tool 628, the present world state 640 and the offset time are passed into the prediction engine 618 which responds with a projection of the present world state 640 and its alternatives into the specified future point in time S(t(f)) where S is the project state at future time t(f).
The prediction engine 618 includes a time manager 650 that is the master time manager for all visual components of interest. It maintains a master wall clock and a real-time clock for each platform and entity of interest. When it receives an offset time instance, it calculates a future clock instance by adding the real-time (current time) to the offset time for each platform or entity of interest. Since real time consistently moves forward, the time manager 650 has the added responsibility of determining how long the projected state is valid for. After the valid time period has expired, the time manager 650 notifies the system that the projected future world state is no longer valid and that a new projection is required.
One or more object model estimators (or predictors) 654 can be provided as a plug-in framework for creating, loading, and managing behavioral models. These models have a one to one correspondence to the data feeds coming into the state aggregator 614. Each object model estimator 654 includes methods and constraints specific to its associated data feed for projecting that particular data feed into the future. Such methods may include a family of prediction and interpolation algorithms that are appropriate for each respective object behavioral model. The prediction algorithms can include, but are not limited to, Kalman filters, Markov filters, Particle filters, Runga-Kutta, Predictor-Corrector, and so forth.
A world state propagator 656 processes an offset time, current state, and the appropriate object model estimators, and propagates them from the present state to a specified future state. This component 656 conducts this action for each object model. Upon completion of all the models, the predicted world state is aggregated at 660 and sent to the world state fusion & rendering pipeline 620 for display at 644. Output from the predicted world state at 660 can also be utilized to update contingency data within the data structures described herein (e.g., via the behavior fields)
What has been described above are examples. It is, of course, not possible to describe every conceivable combination of components or methodologies, but one of ordinary skill in the art will recognize that many further combinations and permutations are possible. Accordingly, the disclosure is intended to embrace all such alterations, modifications, and variations that fall within the scope of this application, including the appended claims. As used herein, the term “includes” means includes but not limited to, the term “including” means including but not limited to. The term “based on” means based at least in part on. Additionally, where the disclosure or claims recite “a,” “an,” “a first,” or “another” element, or the equivalent thereof, it should be interpreted to include one or more than one such element, neither requiring nor excluding two or more such elements.
Cao, Feng, Parsons, William, Oddo, Louis, Parekh, Devang R., Fung, Henry H., Patel, Miteshkumar K.
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